Question

which of the following organisms best illustrates x-selection?
the production of thousands of eggs every spring by frogs
mice that produce three litters of 10 - 15 babies in the course of a summer
a polar bear producing one or two cubs every three years
which of the following will likely decrease a populations size? * 1 point
improving the quality of its habitat
practicing sustainable resource management in its habitat
decreasing the food supply available to the population
if most of the individuals of a human population are in their pre - reproductive years, you would expect the population size to ______ after 20 years. * 1 point
stay the same
increase
decrease
according to this graph of the population growth of fur seals, in what year did the population first reach its carrying capacity? * 1 point

Explanation:

• First question: K - selection is characterized by few offspring with high parental investment. Polar bears having one or two cubs every three years fit this as they invest more in each offspring compared to frogs (many eggs with little care) or mice (more frequent and larger litters but still less investment per offspring than polar bears).
• Second question: Decreasing food supply limits resources for survival and reproduction, likely decreasing population size. Improving habitat quality and sustainable resource management usually support or increase population.
• Third question: If most are in pre - reproductive years (will enter reproductive age soon), they will reproduce in the next 20 years, leading to population increase.

Answer:

• First question: a polar bear producing one or two cubs every three years
• Second question: decreasing the food supply available to the population
• Third question: increase